through the BIO. If it is not then the final block will fail a subsequent
decrypt.
-When decrypting an error on the final block is signalled by a zero
+When decrypting an error on the final block is signaled by a zero
return value from the read operation. A successful decrypt followed
by EOF will also return zero for the final read. BIO_get_cipher_status()
should be called to determine if the decrypt was successful.